public class MyCircularQueue {
    private int[] elem;
    private int front;
    private int rear;

    public MyCircularQueue(int k) {
        this.elem = new int[k];
    }

    public boolean enQueue(int val) {
        if (isFull()) {
            return false;
        }
        elem[rear] = val;
        rear = (rear+1) % elem.length;
        return true;
    }

    public boolean isFull() {
        return (rear+1) % elem.length == front;
    }
    public boolean deQueue() {
        if (isEmpty()) {
            return false;
        }
        front++;
        return true;
    }
    public boolean isEmpty() {
        return rear == front;
    }
    public int Front() {
        if (isEmpty()) {
            return -1;
        }
        return elem[front];
    }
    public int Rear() {
        if (isEmpty()) {
            return -1;
        }
        int index = (rear == 0) ? elem.length-1 : rear-1;
        return elem[index];
    }
}
